Subject-matter which extends the protection


This principle mentioned inA123 (3) EPC applies only after delivery.

Once a patent is issued, an act of a third party that does not constitute an infringement can not become an infringement because of an amendment made after the grant (T1149 / 97 and Directives H-IV 3.1) even if the description would support such a modification.

Basis for assessment

The range extension must be viewed in relation to the previous game (H-IV Guidelines 3.3) that this one

  • the issued one;
  • that maintained modified after opposition;
  • or that resulting from a limitation.


Amendment of claims


This is the simplest case: if a limitation is removed (respectively replaced) in a claim, the protection conferred by the claims increases (respectively, moves) and therefore contravenes theA123 (3) EPC (Directives H-IV 3.1).

At first sight, but without certainty, this only applies to independent claims.

It is possible to replace a restrictive wording with another less restrictive wording if (T371 / 88):

  • this allows to solve problems of clarity ;
  • it is clear from the application that the less restrictive embodiment forms part of the invention and that there has never been any question of excluding it.

It is possible to replace in a claim a piece of information inaccurate by the exact information that is present throughout the rest of the application (T108 / 91).

Case of a non-limiting characteristic

One wonders what happens when a non-limiting feature is removed. 

This can happen in particular if a characteristic targets an object which is not the one claimed (eg "remote control adapted to be used on an OLED television") - the deletion of the characteristic "OLED" has a priori no impact on the remote control).

In this case, and normally, there is no extension of the protection.

Nevertheless, it is necessary to have a holistic interpretation of the claim (ie to analyze the claim as a whole by seeking the goal of the writer) (T1825 / 13).

For example, a licensee sought to delete the term "heat" in the claim " printer print quality control device, in which the printer includes two drying devices for heat drying the ink". Its argument was the fact that the printer which dried with heat was "outside the invention" and that therefore the characteristics of the latter were non-limiting of the device.

The chamber does not agree since, for it and according to the description, the claim should be understood as covering the printer “ printer with a print quality control device and two dryers to heat dry ink". Therefore the deletion of in the heat "ContravenesA123 (3) EPC.

Limitation of a characteristic in an “open” composition

Imagine the following situation in which the claim has " the composition includes less than 5% of metal salts ».

If this characteristic is changed to " the composition includes less than 5% salts metal zinc " , there exists a scope extension behind this apparent limitation (T1360 / 11 or T287 / 11).

Indeed, the copper salts (for example) whose content was limited in the first formulation are no longer limited.

The same situation happens if we have the characteristic " the composition comprises less than 5% of metal salts chosen from copper or zinc salts Which is limited the composition comprises less than 5% of metal salts chosen from copper salts or zinc ": Zinc salts can now be present in any proportion.

Change of claim categories


A change of category is not necessarily inadmissible within the meaning of theA123 (3) EPC (G2 / 88).

Acceptable changes

Are eligible:

Unacceptable changes

Not eligible:

Modification of description / drawings

Changes to the description and drawings may also extend the protection conferred on claims by interpreting them

It is therefore forbidden to add in the course of opposition or during limitation a part of the description or drawings which had been deleted during examination (H-IV Guidelines 3.4).

decision T241 / 02 to moderate this prohibition by indicating that this is possible if the holder seeks to overcome a lack of description.

In addition, if the licensee modifies to provide drawings in order to hand over those originally filed, there may also be a range extension (T1360 / 13), especially in the case where the previous figures were more "obscure", therefore less limiting.

Pliers A123 (2) -A123 (3)


If the applicant / holder has limited his application / patent with a technical feature not disclosed by the application as filed (and therefore contrary toA123 (2) EPC), it will not be able to remove it without extending the scope of its protection (which would be contrary to A123 (3) EPC) (G1 / 93, H-IV 3.5 Guidelines).

Of course, this characteristic must be a technical characteristic.

It is not possible to avoid this trap by removing the feature and limiting the scope with a disclaimer (T1180 / 05).

I can't help but refer to this GIF from @IP_memes

Exceptions to non-technical characteristics

It may happen that the claims are limited, during the procedure, in a non-technical way (eg restriction of the claimed method to only certain times, or to certain parameters only).

In that event, the Boards of Appeal seem to consider that those limitations are not prohibited by theA123 (2) EPC (T1779 / 09): the principle here seems to prevent the holder from falling into the "trap" of A123 (2) EPC and A123 (3) EPC.

Leave a Reply

Your e-mail address will not be published. Required fields are marked *